$PROFILE_PSReadLine.ps1

using namespace System.Management.Automation
using namespace System.Management.Automation.Language

if ($host.Name -eq 'ConsoleHost')
{
    Import-Module PSReadLine
}

Set-PSReadLineOption -PredictionSource History
Set-PSReadLineOption -PredictionViewStyle ListView
Set-PSReadLineOption -EditMode Windows

# 設定按下 Ctrl+d 可以退出 PowerShell 執行環境
Set-PSReadlineKeyHandler -Chord ctrl+d -Function ViExit

# 設定按下 Ctrl+w 可以刪除一個單字
Set-PSReadlineKeyHandler -Chord ctrl+w -Function BackwardDeleteWord

# 設定按下 Ctrl+e 可以移動游標到最後面(End)
Set-PSReadlineKeyHandler -Chord ctrl+e -Function EndOfLine

# 設定按下 Ctrl+a 可以移動游標到最前面(Begin)
Set-PSReadlineKeyHandler -Chord ctrl+a -Function BeginningOfLine

#Set-PSReadLineKeyHandler -Key UpArrow -Function HistorySearchBackward
#Set-PSReadLineKeyHandler -Key DownArrow -Function HistorySearchForward

# This key handler shows the entire or filtered history using Out-GridView. The
# typed text is used as the substring pattern for filtering. A selected command
# is inserted to the command line without invoking. Multiple command selection
# is supported, e.g. selected by Ctrl + Click.
Set-PSReadLineKeyHandler -Key F7 `
                         -BriefDescription History `
                         -LongDescription 'Show command history' `
                         -ScriptBlock {
    $pattern = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$pattern, [ref]$null)
    if ($pattern)
    {
        $pattern = [regex]::Escape($pattern)
    }

    $history = [System.Collections.ArrayList]@(
        $last = ''
        $lines = ''
        foreach ($line in [System.IO.File]::ReadLines((Get-PSReadLineOption).HistorySavePath))
        {
            if ($line.EndsWith('`'))
            {
                $line = $line.Substring(0, $line.Length - 1)
                $lines = if ($lines)
                {
                    "$lines`n$line"
                }
                else
                {
                    $line
                }
                continue
            }

            if ($lines)
            {
                $line = "$lines`n$line"
                $lines = ''
            }

            if (($line -cne $last) -and (!$pattern -or ($line -match $pattern)))
            {
                $last = $line
                $line
            }
        }
    )
    $history.Reverse()

    $command = $history | Out-GridView -Title History -PassThru
    if ($command)
    {
        [Microsoft.PowerShell.PSConsoleReadLine]::RevertLine()
        [Microsoft.PowerShell.PSConsoleReadLine]::Insert(($command -join "`n"))
    }
}


# F1 for help on the command line - naturally
Set-PSReadLineKeyHandler -Key F1 `
                         -BriefDescription CommandHelp `
                         -LongDescription "Open the help window for the current command" `
                         -ScriptBlock {
    param($key, $arg)

    $ast = $null
    $tokens = $null
    $errors = $null
    $cursor = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$ast, [ref]$tokens, [ref]$errors, [ref]$cursor)

    $commandAst = $ast.FindAll( {
        $node = $args[0]
        $node -is [CommandAst] -and
            $node.Extent.StartOffset -le $cursor -and
            $node.Extent.EndOffset -ge $cursor
        }, $true) | Select-Object -Last 1

    if ($commandAst -ne $null)
    {
        $commandName = $commandAst.GetCommandName()
        if ($commandName -ne $null)
        {
            $command = $ExecutionContext.InvokeCommand.GetCommand($commandName, 'All')
            if ($command -is [AliasInfo])
            {
                $commandName = $command.ResolvedCommandName
            }

            if ($commandName -ne $null)
            {
                Get-Help $commandName -ShowWindow
            }
        }
    }
}